A study funded by the Charity Leukemia Research, said that both Olivia and Isabella were found to have "pre-leukemic" cells in their bone marrow but to date, only Olivia had leukemia.
Researches said that this pre-leukemic cell is transferred from one twin to the other in the womb through their umbilical cord.
And that it takes another genetic mutation in early childhood for the cells to cause disease, which happened to Olivia when she was two and that's why she had leukemia, and Isabella does not.
Because of this difference between the twins that enabled the scientist to determine the pre-cancerous stem cells in both girls and then they figure out the sequence of genetic mutations.
The doctors have monitoring Isabella for signs of cancer. They said that if she reaches adolescent and still does not have it, they thought that the rogue cell may disappear and she might not have cancer at all.
